Centerless grinding machine with an automatic feed through the machine



March 4, 1969 J. HOWLES 3,430,392

CENTERLESS GRINDING MACHINE WITH AN AUTOMATIC FEED THROUGH THE MACHINE Filed Dec. 21. 1966 Sheet of 4 INVENTOR- 50 59 04/1/5 J Homes 5 ATTOPNEY March 4, 1969 J. HOWLES 3,430,392

CENTERLESS GRINDING MACHINE WITH AN AUTOMATIC FEED THROUGH THE MACHINE Sheet 2 of 4 Filed Dec. 21 1966 LWENI' 01a. DAN/6L d- HOk/LES a? m g o A: rrow 6y March 4, 1969 D. J. HOWLES 3,430,392

CENTERLESS GRINDING MACHINE WITH AN AUTOMATIC FEED THROUGH THE MACHINE Filed Dec. 21. 1966 Sheet 3 or 4 INVENTOR.

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United States Patent ()fiice 3,430,392 Patented Mar. 4, 1969 3,430,392 CENTERLESS GRINDING MACHINE WITH AN AUTOMATIC FEED THROUGH THE MACHINE Daniel J. Howles, Jamestown, N.Y., assignor to TRW Inc., Cleveland, Ohio, a corporation of Ohio Filed Dec. 21, 1966, Ser. No. 603,611

US. Cl. 51-103 19 Claims Int. Cl. B241) /18 ABSTRACT OF THE DISCLOSURE A centerless grinder for successively moving workpieces axially between a grinding wheel and a regulating wheel. The regulating wheel has circumferentially extending, axially spaced :guide means forming successive positions for workpieces, and has an indexing member also with guide means matching the regulating wheel guide means in two mating positions on axial movement by an actuating member to receive workpieces and to shift workpieces axially.

This invention relates to centerless grinding and is directed particularly to the automatic feeding of a plurality of workpieces through a centerless grinder.

In centerless grinding it is desirable to automatically feed workpieces through the grinding process with a minimum of attention, so that large quantities of workpieces may be rapidly and inexpensively finished. This feeding of the workpieces should be done without requiring the displacement of the grinding wheel or of the work-holding or regulating wheel. It is also desirable that the workpieces be moved through the grinding apparatus with a minimum of handling and movement of the workpieces so that damage to the finished surfaces is avoided. It is, therefore, desirable to move the workpieces generally axially through the grinding apparatus with any contacting of the workpieces performed by machine elements normally engaging the workpieces in the grinding process.

An object of the invention is to provide a centerless grinding machine with an automatic feeding of workpiece through the machine without the variation of the relationship between the grinding wheel and work-holding wheel when the workpieces are indexed in the machine.

Another object of the invention is to provide a centerless grinding machine with automatic feeding of workpieces in which the workpieces are moved generally axially through the machine with a minimum of lateral movement thereto and engagement by machine parts.

Another object of the invention is to provide a centerless grinding machine having an automatic feeding of the workpieces and which will grind workpieces of various configurations, such as cylinders, spheres, cones or the like.

Another object of the invention is to provide a centerless grinding machine having an automatic feeding of the workpieces and which will grind recessed races and internal faces of bearing rings.

Other and further objects and advantages will be apparent from the following description taken in connection with the drawings in which FIG. 1 is a fragmentary side view of the centerless grinding machine from the discharge side illustrating the grinding wheel, workholding or regulating wheel and the indexing member;

FIG. 2 is a front view of the indexing member of the centerless grinding machine;

FIG. 3 is a top view of the indexing member in the indexing position with the mounting and earns;

FIG. 4 is an end view of the indexing member from the discharge side;

FIG. 5 is an inner bottom view of the indexing member;

FIG. 6 is a plane view of the feed groove on the workholding wheel;

FIGS. 7 to 9 diagrammatically illustrate the indexing of the workpieces through the machine;

FIG. 10 illustrates an embodiment for grinding tapered rollers and is a comparative sectional view of the grinding operation and the indexing operation;

FIG. 11 illustrates an embodiment for grinding a cylindrical inner ring with flanges and is a sectional view through the axis of the rings;

FIG. 12 is a front view illustrating the relationship of the cylindrical inner rings with flanges and the supporting blade;

FIG. 13 is a side view illustrating the inner rings in a raised indexing position;

FIG. 14 is an embodiment for grinding of convex spherical inner rings taken along a. section through the axis of the rings;

FIG. 15 is an embodiment for grinding of concave raceways and outside diameters of inner rings and is a section taken through the axis of the rings;

FIG. 16 is an embodiment for grinding balls and is a section taken along the radial plane of the regulating wheel; and

FIG. 17 illustrates a side view of the modification shown in FIG. 16 for grinding balls.

Referring to FIGS. 1 and 2 the grinding machine has a grinding wheel 10 with a cylindrical grinding surface 11, a roller 12 for a roller bearing and a workholding or regulating wheel 13. The grinding wheel "10 may be of a conventional type and is rotated about a center 14 at a constant 'high velocity with the surface 11 moving downwardly at the grinding station as indicated by the arrow A. The roller 12 is supported by a blade 15 and rotate clockwise (FIG. 1) or downwardly in contacting relation with the grinding wheel. The workholding or regulating wheel 13 rotates counterclockwise at the grind ing station as indicated by the arrow B and is, in this embodiment, of a substantially larger size than the grinding wheel 10. The work-holding wheel, however, may be smaller than the grinding wheel depending upon the type of grinding to be performed.

The work-holding wheel 13 has a cylindrical rim \16 connected by spokes 17 to an inner cylindrical hub 18 to form axially extending spaces 19 therebetween. Referring to FIG. 2 the outer surface of the work-holding wheel has flanges 20 parallel to one another and extending radially from the rim 16 to form grooves 21 with work engaging surfaces 22 on the outside of the rim 16. The flange 73 forms a groove 70 with a flange 20. The rim 16 and the flanges 20 have a space 25 extending axially across the entire width of the work-holding wheel and over a circumferential angle of twenty-four degrees through the rim and flanges. An indexing member 26 is positioned in the space 25 to move axially or longitudinally in the space. The indexing member has a circularly curved body 27 (FIGS. 3, 4 and 5) corresponding in curvature to the rim 16 and has radially extending flanges 28 (FIGS. 2 and 3) spaced axially apart the same distance as the flanges 20 to form grooves 29 corresponding in width to the grooves 21. The body portion 27 forms surfaces 30 between the flanges corresponding to the surfaces 22 on the work-holding wheel.

Thus when the flanges 20 and 28 and the grooves 21 and 29 are coincident, the grooves 29 form a continuation or bridge between the ends of the corresponding grooves 21. The body portion has a bracket 31 (FIGS. 3 and 5) mounted on the inner surface 32 and has two inwardly extending mountings 33. The bracket 31 is secured to the body portion 27 of the indexing member 26 by bolts 34 or any other suitable manner. The mountings 33 are spaced axially apart, as illustrated in FIGS. 3 and 5, and are attached to a resilient mounting formed by two leaf springs 36 normally positioned in parallel planes extending radially to the work-holding wheel 13 and the indexing member 26. The leaf springs 36 are secured to the mountings 33 on opposite ends of the bracket 31 by the blocks 37 and bolts 38.

In addition to the space 25 rectangular shaped recesses 40 and 41 are formed longitudinally inward from the sides 23 and 24 in the rim 16, spokes 17 and cylindrical hub 18 opening into the space 19 between the spokes 17 and hub 18. The recess 40 extends in a distance C and recess 41 extends a distance D. The flange 73 has side recesses 73a, 73b.

The other ends of the leaf springs 36 are attached to the bosses 44 and 45 at the bottom of the recesses 40 and 41, and extend outwardly toward the sides to provide longitudinal space for movement of the springs and the bracket 31 on the indexing member 26. The springs are secured to the bosses 44 and 45 by bolts 46 and 47. Springs 36 form the sole support for the indexing member 26 on the work-holding wheel and firmly hold it radially due to the radial width of the springs 36, but permit longitudinal movement of the indexing member in either direction to longitudinal or axial forces applied to the indexing member. The springs 36 normally support the indexing member 26 when in the unflexed position, as illustrated in FIG. 2, with the indexing member projecting approximately half a groove width from the side 23 of the work-holding wheel.

On the side 23 (FIG. 2) of the work-holding wheel the indexing member 26 has two cam members 50 and 51 for the purpose of longitudinally positioning the indexing member on engagement by the fixed roller 52 (FIG. The fixed roller 52 is rotatably mounted on a post 53 (FIG. 1) secured to the frame (not shown) of the grinding machine. The cams 50 and 51 are mounted on the indexing member 26.

The leading cam 51 has a curved finger 54 (FIG. 4) with its center of curvature at the center of the workholding wheel and the cam 50 has a finger 55 extending in the opposite direction from the finger 54 and correspondingly curved about the center of the work-holding wheel with the same radius of curvature.

The indexing member 26 has a flat plate 56 mounted on the inner bottom side 32 by the bolt 56a and extending longitudinally beyond the indexing member to support the earns 50 and 51. The finger 54 is mounted on a block 57 by means of the bolts 58 and the finger 55 is mounted on the block 59 by means of bolts 60. The blocks 57 and 59 function to space the fingers 54 and 55 from the plate 56 in order to avoid interference with the roller 52.

The leading finger 54 of the cam 51 has a sloped surface 62 facing in a direction away from the indexing member 26. As the roller 52 engages this surface on rotation of the work-holding wheel 13, the cam 51 is shifted against the side 23, as illustrated in dash lines of FIG. 5. The indexing member 26 is shifted towards the side 24 of the wheel (FIG. 8) to align all of the flanges and grooves of the indexing member with the flanges and grooves of the work-holding wheel. The indexing member is held in this position as the wheel rotates by the roller 52 engaging the outwardly facing straight guide surface 63 of the finger 54. The surface 63 terminates approximately onefourth of the width of the indexing member 26 and before the midpoint of the indexing member is reached by the roller 52.

The trailing finger 55 of the cam 50 is circumferentially spaced from the finger 54 to form a space 64 in line with the midsection of the indexing member 26 so that the roller 52 is not in engagement either with cam 50 or 51. The indexing member is in a neutral position (FIG. 7). The cam 50 has a sloped surfage 6 5 5) facing inwardly toward the indexing member 26. The intermediate portion of the surface 65 is in line with the projection of the surface 63 on the cam 51. Since the indexing member 26 is not engaged, it assumes the neutral position as shown in FIGS. 2 and 7 so that the roller 52 is circumferentially aligned with the surface 65. On engagement of this surface the roller 52 forces the indexing member 26 away from the side 23, as indicated by the dash lines of FIG. 5. The grooves 29 of the indexing member 26 are moved one groove over from the grooves 21. This positions the left hand or discharge groove 29 outside of the surface 23 of the work-holding wheel (FIG. 9). The roller 52 holds the indexing member 26 in this position by engaging the circumferentially extending surface 66 until the wheel 13 has rotated to position the rollers 12 in the grooves 21 clear of the indexing member 26. The indexing member 26 is then returned to the neutral position by the sloped surface 67 being engaged by the roller 42. This action occurs on each rotation of the work-holding wheel.

The surfaces 22 extend continuously circumferentially around the wheel for holding the rollers 12 at a respective grinding position. Each surface 22 is a spiral with increasing radius in the direction of rotation of the workholding wheel so as to move the roller 12 towards the grinding wheel for a gradual removal of the surface of the roller. The surfaces extend parallel to the surface of the grinding wheel to form the roller into a cylindrical shape. The grooves 21 are parallel and the beginning radius of a succeeding gro'ove sets the roller in relation to the grinding wheel to continue the grinding process where the terminating radius of the previous groove left off. Thus the surfaces 22 increase in radius from the feed position to the discharge position with the metal removal corresponding to the change in radius of the surface 22. The ditference between the radius of the surface at the beginning of the first groove and the terminating radius at the last groove is the total amount of stock removed. The arcuate surfaces 30 on the indexing member are at a slightly less radius than the corresponding surfaces 22 to permit the rollers to drop away from the grinding wheel, as illustrated in FIG. 1. Thus the rollers are moved axially clear of the grinding wheel.

The right hand groove 70 is a feed groove and is illustrated in FIG. 6 with successive positions of a single roller shown for demonstrating the introduction of the roller to the wheel 13. The groove 70 commences at approximately the beginning of the third quadrant before the space 25 and starts at an angle E of 5". The wheel 13 moves in the direction of the arrow B. The rollers to be processed may be supported on an inclined chute 71 (FIG. 1) on the side 24 of the wheel with the end roller engaging the side 24. The rollers 12 may be urged by gravity or other means towards the wheel so that as the groove 70 starts the lead roller 12 remains in engagement with the angled wall 72 and moves longitudinally or axially into overlapping relation with the wheel 13. The flange 73 at the side 24 starts with a tapered portion 74 to form a sloped portion 75 leading into the groove 70. The tapered portion 74 knives off or separates the lead roller from the succeeding rollers in the feed chute 71.

When the roller 12 is in the groove 70 it drops against the blade 15 and is held between the blade 15 and the bottom of groove 70, FIGS. 1 and 6. As the newly fed roller approaches the space 25 the indexing member is forced over the roller '52 engaging the cam 51 to align the grooves 29 and the indexing member with the grooves 21 and 70 on the wheel. When the rollers are completely captive by the indexing member 26, the cam 51 disengages from the roller 52 and assumes its normal intermediate position. The roller 52 then engages the cam 50 to force the indexing member 26 into the discharge position so that the roller in the left hand groove 29 will drop into the discharge chute 76. The captive rollers are carried by the grooves 29 into the grooves 21 to start the grinding process with the roller in the right hand groove and to continue the grinding process for the rollers in the other four grooves.

Thus as the grinding process is completed in each groove 21 a newly fed roller is in position in the groove 70. As illustrated in FIG. 2, the leading cam '51 precedes the indexing member 26 and is of suflicient length to engage the roller 52 before the grinding of the rollers in the grooves 21 is completed. The grooves 29 are in alignment with the grooves 21 and the grooves 70 for receiving the rollers. The trailing cam 50 is mounted and has a length to shift the indexing member and align the grooves 29 with the grooves 21 until the rollers are in the succeeding grooves and the grinding has commenced. The finished roller is dropped from the indexing member to the discharge chute.

In the foregoing embodiment rollers with cylindrical surfaces are ground. However, workpieces having other configurations may be processed in accordance with the invention.

In FIG. a fragmentary sectional view of a grinding wheel 80, regulating or workpiece-holding wheel '81 and an indexing member 82 is shown for grinding tapered rollers 89. The grinding Wheel has a cylindrical grinding surface 83 divided into circumferential portions by ribs 84 forming rounded fillets 85 with the grinding surface 83. The work-holding wheel 81 has flanges 86 defining spaced grooves 87 with circumferential roller supporting surfaces 88 tilted at an angle corresponding to twice the angle of taper of the roller. This positions the roller surfaces engaging the grinding surface 83 parallel thereto. The fillets 85 round the corners of the rollers. As in the previous embodiment the indexing member 82 is at a slightly lesser radius than the wheel 81 to space the rollers from the grinding wheel 80. The rollers are clear of the ribs 84 and thus may be axially indexed to the succeeding grooves with the processed roller being discharged. A Work rest blade 90 supports the rollers both in the grinding and indexing positions.

FIGS. 11 to 13 are fragmentary sectional views illustrating apparatus for grinding inner roller bearing rings 91 having cylindrical recessed races 91a. The races are ground by the grinding wheels 92 having cylindrical grinding surfaces 92a which fit in the recesses to engage the cylindrical races 91a. The regulating or workpieceholding wheel 93 has flanges 94 and raised portions 95. The raised portions have a surface 95a for engaging the races 91a to press the rings against the grinding wheels 92.

A support blade 96 has projections 96a fitting in the recesses and engaging the races 91a to cooperate with the regulating wheel 93 in holding the rings against the grinding wheels. The surfaces 95a are comparable to the surfaces 22 of the roller grinding apparatus and are circumferentially spiral to move the ring 91 against the grinding wheels 92 for stock removal.

The indexing member '97 is similar to the indexing member 26 and has flanges 97a and a cylindrical bottom surface 97b which is recessed so that the rings move away from the grinding wheels 92.

The flanges 91b of the ring are raised clear of the projections 96a on the blade 96 by a lift rod 98. The lift rod moves vertically, as indicated in FIG. 12, to engage the flanges 91b and raise the rings 91, as indicated in FIG. 13. The indexing member 97 has a similar actuating mechanism as indexing member 26 and is thus moved axially to shift the rings to a succeeding groove for further processing. The lift rod 98 then moves downward to rest the rings 91 on the blade 96.

The inner faces 91c and 91d of the flanges 91b may be ground by setting the surface 94a of the flange 94 so as to position the surface 910 against the side of the grinding wheel 92. The opposite surface 91d may be ground in a succeeding position by the surface 94b of the flange 94 engaging the opposite side of the ring 91 and pressing the inner surface 91a against the other side of the grinding wheel 92. The surfaces 94a and 94b are helical in an axial direction to move the rings against the side of the Wheel for removal of the metal. Thus the two inner surfaces of the flanges may be ground.

However, it is preferable to plunge grind the inner faces 91c and 91d. The rings 91 are positioned in relation to the grinding wheels by either the surfaces 94a or the surfaces 94b engaging the rings 91. The surfaces a have two different and successive spiral configurations. The first configuration moves the ring 91 into the respective grinding wheel the depth of the flanges 91b for grinding the inner surfaces 910 and 91d. The following and second configuraiton of the surface 95a is spirally shaped for grinding the race 91a of the ring.'The indexing of the rings is the same. In this preferred method of plunge grinding the inner faces of the flanges the grinding wheels 92 are dressed to the proper width for grinding the surfaces.

In FIG. 14 a front view of an embodiment is illusthan the regulating wheel to move the rings from the trated in which bearing rings 100 have spherical convex surfaces 101 ground by the concave grinding wheels 102 with the rings mounted in the regulating wheel 103 and the indexing member 105 and resting on the support blade 104. The rings 100 are positioned by the concave circumferentially extending surfaces 106 in the regulating wheel 103. The surfaces 106 increase in radius in a similar manner to the surfaces 22 of the embodiment of FIG. 1 to urge the rings against the grinding wheels 102. The rings are indexed in a manner similar to the indexing of the cylindrical rollers. The indexing member 105 has convex surfaces 107 of lesser radius than the surfaces 106 to move the rings 100 away from the grinding wheels 102. Convex rollers may be similarly finshed.

In FIG, 15 an embodiment is illustrated for grinding concave races and outer cylindrical surfaces of an inner ring. The bearing rings are positioned in grooves 116 formed by the radially and circumferentially extending flanges 116a of the regulating wheel 117. The rings have a concave race 118 and outer cylindrical surfaces 119. The grinding wheel 120 has a convex surface portion 121 and cylindrical portions 122 therebetween for grinding the concave race 118 and outer cylindrical surfaces 119 simultaneously. The outer cylindrical surfaces 119 engage the cylindrical and spiral surfaces 126 at the bottom of the grooves 116 for urging the rings against the grinding wheel. The indexing member 124 is similar to the other indexing member and has grooves 125 formed by flanges 125a. The indexing member is at a slightly lesser diameter grinding wheel and clear the lower surface portions 121. The support blade 123 engages the outer cylindrical surfaces 119 which permits the sliding of the rings 115 along the blade. In this embodiment if the outer cylindrical surfaces 119 are not ground, the support blade 123 would carry projections (not shown) for solely engaging the concave races 118. A rod similar to rod 98 would then be required to raise the rings 115 from overlapping with the projections on the blade.

In FIGS. 16 and 17 spherical bearing balls are held in grooves 132 formed by axially sloped walls 134 on the workpiece-holding or regulating wheel 131 in cooperation with the support blade 133. The grinding wheel 135 has a cylindrical surface 136. In order to rotate the balls 130 for a uniform grinding a belt 137 engages the balls. The belt travels laterally to the grooves 132 for imparting a spin to the balls 130 transverse to the spin produced by the grinding wheel 135. The radii of the walls 134 are increased to urge the balls against the grinding wheel. The halls 130 are indexed in a similar manner as the cylindrical rollers with the indexing member 138 (FIG. 16) having grooves 139. The grooves 139 are formed by axially sloped walls 140 having a lesser radii than the walls 134 to relieve the balls from the grinding wheel.

It is thus seen from the foregoing description that a centerless grinding machine has been developed in which various configurations of workpieces may be moved continuously and automatically through the grinding machine. The rollers 12 may be loaded from time to time in the feed chute 71 and the collected finished rollers are removed as needs require. Very little attention need be given the grinding process except for an occasional examination that the process is properly proceeding.

The workpieces are moved axially through the machine with a minimum of impact contact between the finished surfaces and the grinding and feed apparatus. The surfaces being finished are in contact with the annular or bottom surfaces of the groove or of the indexing member, the latter being a segment of the former slightly recessed and separate from the bottom surfaces of the grooves of the work-holding or regulating wheel. Also, in addition the support blade is engaged by the workpiece and slid therealong in instances where there are no projections to be cleared. In the latter instances no other tool engages the surface being finished. Thus the finished surfaces are isolated from abrasion or damage due to the transfer of the workpieces.

Further, as noted from the drawings and the description, the indexing member is of a relatively simple construction resiliently mounted so as not to shift radially but solely to move axially. The grooves 21 formed by the flanges 20 and 22 are a guide means for preventing the workpiece from moving axially and to urge the workpiece against the grinding wheel for removal of the desired amount of metal from the surfaces to beprocessed. The starting radius of a surface 22. is equal to or slightly less than the terminating radius of the previous surface 22 so that the grinding of the workpiece starts where the previous grinding left off.

It is thus seen that the transfer of the workpieces is accomplished without varying the spacing between the centers of rotation of the grinding wheel and the regulating or workpiece-holding wheel. Thus the proper relationship between these two wheels is maintained for successive grinding of workpieces with occasional adjustment for the wear of the grinding wheel. This ensures that each workpiece will be ground to the same dimension.

Various modifications and changes may be made in the foregoing embodiments and the invention may be applied to other types of workpieces which may be finished by a centerless grinding process. The invention is set forth in the appended claims.

I claim:

1. A centerless grinder automatically feeding workpieces therethrough comprising a rotatable grinding wheel, a rotatable regulating wheel having means forming a plurality of circumferentially extending guide means facing said grinding wheel for holding workpieces a ainst the grinding wheel, said regulating wheel having an indexing member mounted thereon to move in an axial direction and to rotate with said wheel, a plurality of guide means on said indexing member mating with said regulating wheel guide means in two mating positions by axial movement of said indexing member, actuating means for positioning said indexing member in said first mating relation to receive workpieces from said regulating wheel guide means and position said indexing member guide means in a second mating relation with said regulating wheel guide means to deliver the workpieces to a succeeding regulating wheel guide means for successively moving workpieces axially through the grinder.

2. A centerless grinder as set forth in claim 1 wherein said guide means on said indexing member are radially recessed in relation to said guide means on said regulating wheel to move workpieces from the grinding wheel when supported by said indexing member.

3. A centerless grinder as set forth in claim 1 wherein each of said regulating wheel guide means has a spiral supporting surface increasing in radius in the direction of rotation.

4. A centerless grinder as set forth in claim 3 wherein said supporting surface of said succeeding regul ting wheel guide means has a larger radius than said supporting surface of the preceding regulating wheel guide means to remove further material from a workpiece.

5. A centerless grinder as set forth in claim 1 wherein said regulating wheel guide means are channel shaped and have spiral supporting surfaces increasing in radius in the direction of rotation.

6. A centerless grinder as set forth in claim 1 wherein said regulating wheel guide means are parallel and separate and said indexing member interconnects adjacent guide means on said regulating wheel by axial movement of said indexing member from one mating position to the other.

7. A centerless grinder automatically feeding Workpieces therethrough comprising a supporting frame, a grinding Wheel rotatably mounted on said frame, a regulating wheel rotatably mounted on said frame about an axis and having a plurality of circumferentially extending guide means facing said grinding wheel for holding workpieces against said grinding wheel, means between said regulating wheel and said grinding wheel for supporting workpieces between said wheels, said regulating wheel having an axially extending space intersecting said guide means, an indexing member mounted in said space to move axially and having a plurality of guide means mateable with said regulating wheel guide means, actuating means attached to said indexing member to position said guide means of said indexing member in a first mating relation with said regulating wheel for receiving workpieces from said regulating wheel guide means and in a second mating relation with said regulating wheel to deliver workpieces to succeeding regulating wheel guide means for successively moving workpieces axially through the grinder.

8. A centerless grinder as set forth in claim 7 wherein said regulating wheel has a feed means with an entering portion at an angle for receiving and axially guiding workpieces into position for transference to the indexing member.

9. A centerless grinder as set forth in claim 7 wherein said guide means of said indexing member have a slightly lesser "radius than the guide means of said regulating wheel for spacing workpieces from the grinding wheel on axial indexing.

10. A centerless grinder as set forth in claim 7 wherein said indexing member is resiliently mounted to move solely in an axial direction.

11. A centerless grinder as set forth in claim 10 wherein a cam roller is mounted on said frame and cams extending in opposite circumferential directions are mounted on said indexing member for engaging said roller to shift said indexing member between the first and second mating relations.

12. A centerless grinder as set forth in claim 7 wherein each of said regulating wheel guide means has axially sloped supporting surfaces increasing in radius in direction of rotation of said regulating wheel for supporting workpieces having conically shaped surfaces.

13. A centerless grinder as set forth in claim 7 wherein said grinding wheel has axially spaced grinding means and each of said guide means has circumferentially extending raised portions for engaging and holding inner races of bearing rings in grinding relation with said axially spaced grinding means.

14. A centerless grinder as set forth in claim 13 wherein said regulating wheel guide means have a plurality of radially and circumferentially extending flanges between said raised portions for positioning bearing rings in relation to the grinding means for grinding inwardly facing flange surfaces of bearing rings.

15. A centerless grinder as set forth in claim 7 wherein said regulating wheel guide means comprise radially sloped circumferentially extending surfaces forming circumferential grooves for holding spherical balls in grinding relation with said grinding wheel.

16. A centerless grinder as set forth in claim 15 wherein belt means is provided extending and movable in an axial direction between said grinding wheel and said regulating wheel for engaging and rotating bearing balls to grind spherical surfaces thereon.

17. A centerless grinder as set forth in claim 7 wherein said grinding wheel has concave circumferentially extending axially spaced grinding surfaces and said regulating Wheel guide means have circumferentially extending concave surfaces for supporting inner spherical rings in grinding relation with said concave grinding surfaces.

18. A centerless grinder as set forth in claim 7 wherein said grinding Wheel has circumferentially extending axially spaced convex surfaces for grinding inner bearing ball races on inner bearing rings.

19. A centerless grinder automatically feeding workpieces therethrough comprising a supporting frame, a grinding wheel rotatably mounted on said frame and having a cylindrical grinding surface, a regulating wheel rotatably mounted on said frame about an axis parallel to the axis of the grinding wheel, said regulating wheel having a space extending axially across the width of the regulating wheel and having a plurality of radially and circumferentially extending flanges terminating at said space and axially separated to form grooves for axially holding workpieces in axial spaced relation, spiral surfaces between said flanges extending parallel to said cylindrical grinding surface and having radii gradually increasing in direction of rotation of said regulating wheel for feeding workpieces against said cylindrical grinding surface for removal of material from workpieces with the initial radius of a given spiral surface being equal to or slightly less than the terminating spiral surface of an adjacent preceding surface, an arcuate indexing member positioned in said space and extending axially therethrough having a plurality of radially and circumferentially extending flanges axially spaced for mating with the flanges of said regulating wheel and having surfaces between said flanges of lesser radius than the radii of the surfaces of said regulating wheel for moving a workpiece away from said cylindrical grinding surface when supported by said indexing member, means for supporting said indexing member to move axially relative to said regulating wheel, a cam roller mounted on said frame adjacent to said space, a leading cam and a trailing cam mounted on said indexing member for shifting said indexing member to a first mating relation between said indexing member and said regulating wheel for receiving workpieces on said wheel and shifting to a second mating position on said trailing cam engaging said cam roller for feeding the workpieces to succeeding grooves for continued grinding of said workpieces while maintaining the spacing of the axes of said grinding wheel and said regulating wheel in a given relation.

References Cited UNITED STATES PATENTS LESTER M. SWINGLE, Primary Examiner. 

